Wathilah bin Al-Asqa' (May Allah be pleased with him) said:
The Messenger of Allah (ﷺ) said, "Do not express pleasure at the misfortune of a (Muslim) brother lest Allah should bestow mercy upon him and make you suffer from a misfortune."[At- Tirmidhi]. (RU)
App reference (RU): Book 18, Hadith 67 (RU)
Arabic/English book reference (RU): Book 18, Hadith 1577 (RU)